1 800 radiator refused to warranty their product benicia, California

purchased a radiator for a customers car, it lasted 3 weeks and started leaking. recieved another it lasted 1 week and started leaking. was told the car must be building up to much pressure so they would not warranty nor refund my purchase. this after I explained that the new radiator cap was releasing pressure at 15 and  one half pounds as it should so there was no way it was building up too much pressure. they still refused to do anything so I had to purchase a radiator for the customer elsewhere.